Various types of utility knives are known including U.S. Pat. No. 4,227,306 Meshulam which mounts two different kinds of blades and has a safety feature which prevents mounting blades at opposite ends at the same time. U.S. Pat. No. 4,602,433 to Whiting shows a wallpaper knife having a shape which controls the angle between blade and material to be cut. U.S. Pat. No. 4,805,304 to Knoop describes an improved knife having safety and use features which can be used by left or right handed persons.
None of the prior art disclosures show the combination of features and capabilities of the instant invention. It is the applicants opinion that the unique combination of elements used in the present invention contribute to an improved device which is both quite unique and extermely useful.